Multiple Ancillary Services Provision by Distributed Energy Resources in Active Distribution Networks

Abstract

The electric power system is currently experiencing radical changes stemming from the increasing share of renewable energy resources and the consequent decommissioning of conventional power plants based on synchronous generators. Since the principal providers of ancillary services are being phased out, new flexibility and reserve providers are needed. The proliferation of Distributed Energy Resources (DERs) in modern distribution networks has opened new possibilities for distribution system operators, enabling them to fill the market gap by harnessing the DER flexibility. This paper introduces a novel centralized MPC-based controller that enables the concurrent provision of voltage support, primary and secondary frequency control by adjusting the setpoints of a heterogeneous group of DERs in active distribution grids. The input-multirate control framework is used to accommodate the distinct timescales and provision requirements of each ancillary service and to ensure that the available resources are properly allocated. Furthermore, an efficient way for incorporating network constraints in the formulation is proposed, where network decomposition is applied to a linear power flow formulation together with network reduction. In addition, different timescale dynamics of the employed DERs and their capability curves are included. The performance of the proposed controller is evaluated on several case studies via dynamic simulations of the IEEE 33-bus system.

Control Systems for Low-Inertia Power Grids: A Survey on Virtual Power Plants

“…Traditional SC strategies used for the control and coordination of MAPS and multi-MG systems, often rely on centralized topologies that require the measurements of all the DERs in the VPP to fulfill the control goals in (4), see [114], [202], [203]. For instance, [204] and [205] use cascades of fractional-order Proportional-Integral-Derivative (PID) controllers with parameters tuned through optimization-based techniques to obtain centralized controllers capable of reducing frequency deviations in multimicrogrid linear systems.…”

Fast Mapping of Flexibility Regions at TSO-DSO Interfaces under Uncertainty

“…To gain insights into the flexibility of the network around an operating point, we deploy the superposition principle for linear circuits [14]. It is customary to assume that the initial state of the network is known (e.g., via state estimation techniques), represented by initial voltage V init P C n , branch current I init P C n and DER injection pp init , q init q P R 2n values.…”

Safe Reinforcement Learning for Strategic Bidding of Virtual Power Plants in Day-Ahead Markets

“…Growing environmental concerns and advancements in communication and monitoring technologies have led to the increased deployment of Distributed Energy Resources (DERs) in power networks [1], comprising renewable energy sources and prosumers. The market integration of these units is facilitated by their large-scale aggregation under financial entities, commonly known as Virtual Power Plants (VPPs), which have the capacity for trading in wholesale electricity markets [2], [3]. As a self-interested market participant, a VPP aims at maximizing its own profit generated by its market participation and the fulfillment of contractual obligations towards its internal customers.…”